Visualizing Fluorescence: Using a Homemade Fluorescence "Microscope" to View Latent Fingerprints on Paper

Area of Science:

• Optics and Photonics
• Forensic Science
• Educational Technology

Background:

• Fluorescence detection is a fundamental principle in various scientific disciplines.
• Access to specialized equipment for fluorescence imaging can be a barrier in educational settings.
• Developing low-cost, accessible tools is crucial for enhancing science education.

Purpose of the Study:

• To describe the construction and application of an inexpensive handheld fluorescence imager.
• To provide an accessible teaching tool for understanding fluorescence detection principles.
• To demonstrate the imager's utility in visualizing fluorescent samples.

Main Methods:

• Constructed a handheld fluorescence imager using poly(vinyl chloride) (PVC) pipe and other affordable components.
• Incorporated interchangeable optical filters to select specific excitation and emission wavelengths.
• Demonstrated the imager's function by visualizing lawsone-dyed fingerprints on paper.

Main Results:

• The fluorescence imager was successfully built for under $300.
• Lawsone-dyed fingerprints fluoresced red when illuminated with green light, as observed through the imager.
• Fluorescence could be viewed directly by eye or captured using a camera.

Conclusions:

• The developed handheld fluorescence imager is a cost-effective and functional tool for educational purposes.
• It effectively demonstrates the principles of fluorescence detection and imaging.
• This accessible instrument can enhance learning experiences in science education and forensic science.